1. Field of the Invention
This invention relates to the manufacture of melt spun synthetic fibers having temperature regulation properties, the melt spun fibers being formed from polymer-based concentrate pellets that have Phase Change Materials (PCMs) therein.
2. Description of the Related Art
Many fabric materials are made from synthetic fibers. Two processes—a wet solution process and a melt spun process—are generally used for making synthetic fibers. The wet solution process is generally used to form acrylic fibers, while the melt spun process is used to form nylons, polyesters, polypropylenes, and other similar type fibers. A large portion of the fibers that are used in the textile industry are made via the melt spun process.
As is well known, nylon is a family of polyamide polymers characterized by the presence of the amide group CONH; polyester fiber is a fiber in which the fiber-forming substance is a long chain synthetic polymer composed of at least 85-percent by weight of an ester of a dihydric alcohol and terephthalic acid; and polypropylene (C3H5) is a synthetic crystalline thermoplastic polymer having a molecular weight of about 40,000 or more.
The melt spun manufacturing process generally involves passing a melted polymeric material or pellets through a device known as a spinneret, to thereby form individual polymeric fibers. The fibers are then made into a filament/strand, or into a cut staple. After the fibers have been formed, the fibers can be used to make non-woven material, or alternatively, the fibers can be wound into a yarn that is comprised of individual fibers, the yarn to be used thereafter in the weaving or knitting of a fabric material.
In order to provide a thermal regulation property to fabric materials, microencapsulated phase change materials (microPCMs or mPCMs) have been incorporated into acrylic fibers that were made using an aqueous batch (solution) process. However, with respect to synthetic fibers that are made by the melt spun manufacturing process wherein excessive amounts of volatile materials should not be present, conventional aqueous batch methods for incorporating mPCMs into the fibers are problematic.
It is against this background that embodiments of the present invention were developed.